5h-dibenzo(a,d)cyclohepten-10-ylpiperazine derivatives

ABSTRACT

NEW EN-AMINES OF THE FORMULA:   10-(R1-(1,4-PIPERAZINYLENE)-),   R-5H-DIBENZO(A,D)CYCLOHEPTENE   IN WHICH R MAY BE HYDROGEN, HALOGEN, OR LOWER ALKYL, AND R1 REPRESENTS A NITROGEN-CONTAINING SUBSTITUENT, PREFERABLY A CARBOXYAMIDE OR A THIOCARBAMIDE. THESE NEW COMPOUNDS ARE USEFUL BECAUSE OF THEIR PHARMACOLOGICAL ACTIVITIES WHICH INCLUDE MUSCLE RELAXING, ANTI-INFLAMMATORY, ANTI-PYRETIC, ANALGESIC, AND SEDATIVE ACTION. A PREFERRED METHOD OF MAKING THE NEW COMPOUNDS IS DESCRIBED.

United States Patent ABSTRACT OF THE DISCLOSURE New en-amines of the formula:

in which R may be hydrogen, halogen, or lower alkyl, and R represents a nitrogen-containing substituent, preferably a carboxamide or a thiocarbamide. These new compounds are useful because of their pharmacological activities which include muscle relaxing, anti-inflammatory, anti-pyretic, analgesic, and sedative action. A preferred method of making the new compounds is described.

The present invention relates to new en-amines having the following characteristic group:

[.1 QVW in which R is hydrogen, halogen, or lower alkyl, and R represents a nitrogen-containing substituent, preferably a carboxamide or a thiocarbamide.

Compounds having the above-indicated general formula are useful for several purposes on account of their pharmacological activities which are dependent upon the substituent groups R and R More specifically, their pharmacological activity makes them useful primarily as therapeutic agents. These pharmacological activities include muscle relaxing, anti-inflammatory, anti-pyretic, analgesic, and sedative actions.

Preferably, the new compounds of the present invention are prepared by the action of a suitable alkylating, acylating, or arylating agent on the secondary amino group of the piperazine moiety of N-[5H-dibenzo(a,d)cycloheptene-lO-yl]-piperazine. If desired, however, these same compounds can be made by reacting an appropriately substituted piperazine with a 10,11-dihydro-5H-dibenzo (a,d)cycloheptene-lO-one or a -bromo-5H-dibenzo(a,d) cycloheptene.

The preferred method of preparing the compounds of the present invention is as follows: To the N-substituted piperazine derivative dissolved in an anhydrous aprotic 3,575,980 Patented Apr. 20, 1971 solvent, such as benzene, toluene, or other aromatic or aliphatic hydrocarbon or ethyl ether, is added the alkylating, arylating, or acylating agent if necessary in the presence of a suitable base, such as anhydrous sodium carbonate or bicarbonate, or other basic alkali metal salt or alcoholate or organic tertiary nitrogen base, such as pyridine, alkylpiperidine, triethylamine, or anionic ion exchange resin. The reaction temperature can be chosen in the range from 0 C. to boiling temperature of the solvent, and the reaction time is between 1 hour and 24 hours, depending on the reactivity of the compounds involved in the reaction. The reaction mixture is extracted with a water non-miscible solvent, such as ethyl ether, ethyl acetate, benzene, toluene, chloroform, or other. The organic layer is concentrated and the residue crystallized from a suitable solvent, such as benzene, methanol, or ethyl acetate.

The most pertinent prior art known to applicants includes the publication by W. Tochtermann et al., Ber. 97, 1318 (1964). The Tochtermann et a1. publication describes the synthesis of piperidide but not piperazine derivatives however. Belgian Patent 678,483 issued recently to Rhone-Poulenc on dibenzocycloheptatriene derivatives describes certain en-amines which, however, do not have a nitrogen-containing substituent, R on the piperazine moiety.

The invention will be illustrated now by examples showing the preparation of a number of the compounds of the present invention.

EXAMPLE I N-[5H-dibenzo(a,d) cyclohepten-10-yl]-N'- (N-methylacetamide) -piperazine 52 grams (249 mmol.) 10,11-dihydro-5H-dibenzo(a,d)

cyclohepten-lO-one,

129.2 grams (1499 mmol.) piperazine, and

43 grams (226 mmol.) p-toluenesulfonic acid monohydrate were dissolved in 1200 m1. anhydrous toluene.

The solution was refluxed for hours, separating off the formed water with a Dean-Stark trap. The cooled solution was partitioned between toluene and water; the toluene solution was washed with water and extracted with a 0.1 N solution of maleic acid. The cooled acid solution was made alkaline with a saturated solution of NaHCO and the oil which separated was extracted with ethyl ether. The organic solution was washed with water until neutral, dried over Na SO and distilled. The oily dark residue was crystallized from ethyl ether yielding 48 grams of N-[5H-dibenzo(a,d) cyclohepten-10-yl]-piperazine with a melting point of to 117 C.

To a solution of 5.52 grams (20 mmol.) N-[5H-dibenzo(a,d)cyclohepten-10 yl]-piperazine in 60 ml. anhydrous benzene were added 10 grams (100 mmol.) anhydrous Na CO and 2.36 grams (22 mmol.) N-methylchloroacetamide.

The mixture was refluxed under stirring for 24 hours. After cooling, it was poured over crushed ice and extracted with benzene. The aqueous phase was discarded. The organic phase was washed with water until neutral, dried over Na SO and distilled under vacuum (water pump). The solid residue was crystallized from ethyl acetate yielding 6.5 grams of white crystals with a melting point of 198 to 200 C.

U.V. in ethanol 95% A max.=301 III/1.; e=13,l00

N. J. Leonard et aL, J. Am. Chem. Soc, 77, 5078 (1955).

3 EXAMPLE II N- Hdibenzo a,d) cyclohepten- -yl] -N- (N-ethylacetamide -piperazine To a solution of 22.11 grams (80 mmol.) N-[5H-dibenzo(a,d)cyclohepten-l O-yl] -piperazine in 250 ml. anhydrous benzene were added 42.4 grams (400 mmol.) anhydrous Na CO and 10.7 grams (88 mmol.) N-ethylchloroacetamide.

The mixture was refluxed under stirring for 24 hours. After cooling, it was poured over crushed ice, and then extracted with benzene. The benzene phase was washed with water until neutral, dried over anhydrous Na SO' and the solvent distilled under vacuum (water pump). The residue was crystallized from ethanol yielding 23 grams of compound with a melting point of 170 to 172 C.

U.V. in ethanol 95% EXAMPLE III N- [SH-dibenzo a,d cycloheptenl O-yl] -N'- N-npropylacetamide -piperazine To a solution of 22.11 (80 mmol.) N-[SH-dibenzo (a,d)cyclohepten-IO- yl]-piperazine in 250 ml. anhydrous benzene were added 42.4 grams (400 mmol.) anhydrous Na CO and 11.9 grams (88 mmol.) N-n-propylchloroacetamide.

The mixture was refluxed for 24 hours under efficient stirring, cooled, and poured over crushed ice, and then extracted With benzene. The benzene phase was washed with water until neutral, dried over anhydrous Na SO and the solvent distilled under vacuum (water pump). The residue was crystallized from benzene/petroleum ether (40 to 70 C.) yielding 17 grams of compound with a melting point of 124 to 126 C.

U.V. in ethanol 95% A =302 m e=12,300

EXAMPLE IV N- [SH-dibenzo (a,d)cyclohepten-lO-yl] -N'- [N,N- dimethylacetarnide] -piperazine To a solution of 22.11 grams (80 mmol.) N-[5H-dibenzo(a,d)cyclohepten- 10-yl] -piperazine in 250 ml. benzene were added 42.4 grams (400 mmol.) anhydrous Na CO and 10.7 grams (88 mmol.) N,N-dimethylchloroacetamide.

EXAMPLE V N-[SH-dibenzo(a,d)cyclohepten-10-yl]-N'-nbutylcarboxamide-piperazine 2.76 grams (10 mmol.) N-[5H-dibenzo(a,d)cycloheptenl0-yl]-piperazine and 1.98 grams mmol.) n-butyl isocyanate were dissolved 70 ml. anhydrous benzene.

The solution was left at room temperature for 48 hours and then at 4 C. for 10 hours. The 'white crystalline precipitate was filtered off, washed with cold benzene, and then dried. The obtained 2 grams were crystallized from methanol and had a melting point of 182 to 183 C.

U.V. in ethanol EXAMPLE VI N-[SH-dibenzo (a,d cyclohepten-10 yl] -.piperazine- N -yl-phenylcarboxamide 1 gram 3.6 mmol.) N- [5Hdibenzo(a,d)cyclohepten-lO- yll-piperazine and 0.86 gram (7.2 mmol.) phenyl isocyanatc in 27 ml. anhydrous benzene were left overnight at room temperature. The mixture was cooled at 4 C., and the obtained precipitate was filtered off, dissolved in chloroform, filtered through a small layer of A1 0 and crystallized from benzene-methanol yielding 0.62 gram of compound with a melting point of 212 to 214 C.

U.V. in ethanol 95 M :239 m e=32,900

A =299 111,11; e=l3,500

EXAMPLE VII N- 5 H-dibenzo a,d) cycloheptenl O-yl] -piperazine- N-ylo-chlorophenylcarboxamide) 1 gram (3.6 mmol.) N- [5H-dibenzo(a,d)cyclohepten-lO- yl]-piperazine and 1.1 grams 7.2 mmol.) o-chlorophenyl isocyanate in 27 ml. anhydrous benzene were left at room temperature overnight. The obtained white crystalline precipitate was filtered, yielding 1 gram of compound which, crystallized from chloroform-methanol, had a melting point of 189 to 192 C.

U.V. in ethanol 95 A 234 mu; 6: 27,000

EXAMPLE VIII N- 5H-dibenzo( a,d cyclohepten-l O-yl] -piperazine- N-yl- (p-chlorophenylcarboxamide) 1 gram (3.6 mmol.) N-[5H-dibenzo(a,d)cyclohepten-10- yl]piperazine and 1.1 grams p-chlorophenyl isocyanate (7.2 mmol.) in

27 ml. anhydrous benzene were left overnight at room temperature. The precipitated white crystals were filtered. Yield was 1.4 grams (crystallized from chloroform-methanol) with a melting point of 189 to 192 C.

U.V. in ethanol 95 X =247.5 my; e=37,000

EXAMPLE IX N-[5H-dibenzo(a,d) cyclohepten-lO-yl]-piperazine- N'-yl- (m-chlorophenylcarboxamide) 1 gram (3.6 mmol.) N-[SH-dibenzo(a,d)cyclohepten-10- yl]-piperazine and 1.1 grams (7.2 mmol.) m-chlorophenyl isocyanate in 27 ml.

anhydrous benzene were left overnight at room temperature. Petroleum ether (10 ml.) was added and, after some hours, the crystalline precipitate was filtered off. It was crystallized from chloroform-methanol yielding 0.8 gram of compound with a melting point of 182 to 185 C.

U.V. in ethanol 95% A =245 m t; e=33,800

5 EXAMPLE x N- SH-dibenzo a,d) cyclohepten-lO-yl] piperazine- Nyl-phenylthiocarboxamide 2 grams (7.2 mmol.) N-[5H-dibenzo(a,d)cycloheptenl-yl]-piperazine were dissolved in 25 ml. anhydrous benzene and to this was added 2.2 ml. (33 mmol.) acrylonitrile were dissolved in 10 ml. anhydrous benzene and it was kept at room temperature for 12 hours. The white solid precipitate which was formed during the reaction was filtered off, washed with benzene, and dried. The 2.5 grams that were obtained were crystallized from chloroform-methanol yielding 1.48 grams of compound with a melting point of 210 to 214 C.

U.V. in ethanol 95% x max.=250 m e=25,700

EXAMPLE XI N-[SH-dibenzo (a,d) cyclohepten-10-yl]-N-([3- cyanoethyl) piperazine 1.2 grams (4.3 mmol.) N-[H-dibenzo(a,d)cycloheptenl0-yl]-piperazine and 2.2 ml. (33 mmol.) acrylonitrile where dissolved in ml.

anhydrous benzene and refluxed for 15 hours. The solution was concentrated under vacuum (water pump). The residue was crystallized from chloroform-methanol yielding 0.88 gram of compound with a melting point of 143 to 145 C.

U.V. in ethanol 95% max.=302 m 6: 13,200

EXAMPLE XII N-[SH-dibenzo (a,d) cyclohepten-10-yl]-N'-3- picolylpiperazine To 2 grams (7.2 mmol.) of N-[5H-dibenzo(a,d) cyclohepten-10-yl]-piperazine dissolved in ml. of ethanol containing 4.6 grams of anhydrous Na CO were slowly added, under stirring 1.3 grams (7.9 mmol.) 3-chloromethylpyridine hydrochloride dissolved in ml. of ethanol. The mixture was refluxed under stirring for 18 hours. It was cooled, poured into water, and the obtained precipitate filtered off, washed with water, and dried. It was crystallized from chloroform-ethanol yielding 0.8 gram of white crystals with a melting point of 208 to 212 C.

U.V. in ethanol 95% k max.=30l my; e=l3,400

EXAMPLE XIII N- SH-dib enzo (a,d) cyclohepten-10-yl]-N-3 diethylaminoethyl-piperaziue A mixture of 3 grams (14.7 mmol.) 10,11-dihydro-5H-dibenzo(a,d)

cyclohepten-lO-one,

5.3 grams (28.6 mmol.) N-(2-diethylaminoethyl)- piperazine, and

1.43 grams (7.5 mmol.) p-toluenesulfonic acid monohydrate was left at 160 C. for 47 hours, allowing the water which was formed during the reaction to distill off. The cooled reaction mixture was partitioned between ethyl ether and a saturated solution of NaHCO The organic phase was washed with water until neutral, extracted with a 0.1 N maleic acid solution. The acid phase was made alkaline with a saturated solution of NaHCO' and extracted in ether. This organic phase was washed with water until neutral, dried over anhydrous Na SO and the solvent distilled off. The residue (3 grams) was dissolved in petroleum ether, filtered through a small layer of A1 0 activity 1, neutral, and the solvent distilled 6 off. The residue was crystallized from petroleum ether yielding 1.2 grams of compound in the form of white crystals with a melting point of 68 to 70 C.

U.V. in ethanol 95 A max.:301 III/L; e=13,400

EXAMPLE XIV N-[S-methyl-SH-dibenzo (a,d)cyclohepten-10-yl]-N'- (N-ethylacetamide) piperazine To a solution of 10 grams (34.4 mmol.) N-[8-methyl-5H-dibenzo(a,d)

cyclohepten-lO-yl]piperazine in 200 ml. anhydrous benzene were added 21.2 grams (200 mmol.) anhydrous Na CO and 5 grams (41.2 mmol.) N-ethylchloroacetamide.

EXAMPLE XV N- 8-chloro-5H-dibenzo a,d cyclohepten-10-yl]-N- (N-ethylacetamide)piperazine 6.5 grams (20.9 mmol.) N-[8-chloro-5H-dibenzo(a,d)

cyclohepten-lO-yl]piperazine,

3.2 grams (26.3 mmol.) N-ethyl-chloroacetamide, and

13 grams (122 mmol.) anhydrous Na CO in 50 ml. anhydrous benzene were refluxed under stirring for 24 hours. The cooled mixture was poured into water. The benzene phase was separated and washed with water until neutral, dried over anhydrous Na SO and then distilled oif. The residue was crystallized from methanol yielding 3.3 grams with a melting point of 154 C. (decomposition).

U.V. in ethanol 95 7t max.=305 m r; e=ll,500

The pharmacological activity of the above compounds is shown in the following tables.

TABLE I Spontaneous motility (mouse) Method: Dews Administration route: per os Dose: /5 LD Compound of: iPercent reduction of passages Example I -76 Example II -84 Example III Example IV '-93 Example XI 94 TABLE II Anti-inflammatory activity (rat) Method: Carrageenan oedema Administration route: per os Dose: /5 LD Compound of: Percent reduction of oedema Example I -70 Example III -90 Example IV 87 Example XI 67 TABLE III Hypothermia (rat) Administration route: per os Dose: /5 LD Mod. body temp.

Compound of: C. after (time) Example I 1.4 (1 hour) Example II 1.8 (2 hours) Example III l.3 (1 hour) Example XI 1.4 (1 hour) TABLE IV Analgesic activity (mouse) Method: Hot plate Administration route: per os Dose: /s LD Percent time Compound of Modification Example I +331 Example II +351 'Example III +371 Example IV +536 TABLE V Myorelaxing activity (mouse) Administration route: per os Dose: /5 LD Percent of fallen Compound of: animals Example II 60 Example III 60 Example IV 100 What is claimed is:

1. N-[5H-dibeuzo(a,d)cyclohepten 1O y1]N'-(N- methylacetamide) -piperazine.

2. N- [SH dibenzo(a,d)cyclohepten-10-yl]-N'-[N,N- dimethylacetamide] -piperazine.

3. N-[SH dibenzo(a,d)cyclohepten-lO-yl]-piperazine- N'-yl-phenylcarboxamide.

4. N-[8-chloro-5H-dibeuzo(a,d)cyclohepten 10 y1]- N'-(N-ethylacetamide)-piperazine.

5. A 5H-dibenzo(a,d)cyclohepten l0 yl-piperazine compound having the formula wherein R is hydrogen, halogen or lower alkyl and R is (lower) alkyl carboxamide, di(lower)alkyl carboxamide, (lower)alkyl acetamide, di(lower)alkyl acetamide, phenylcarboxamide and halogen substituted phenylcarboxamide.

6.The compound of claim 5 which is N-[SH-dibeuzo- (a,d)cyclohepten-10-yl] N (N-ethylacetamide)-piperazlne.

7. The compound of claim 5 which is N-[SH-dibenzo- (a,d)cyclohepten-10-yl] N (N-n-propylacetamide)- piperazine.

8. The compound of claim 5- vvhich is N-[SI-I-dibeuzo- (a,d)cyclohepten 10 yl]-N-n-butylcarboxamide-piperazme.

9. The compound of claim 5 which is N-[S-methyl-SH- dibenzo(a,d)cyclohepten-10-yl]-N-(N ethylacetamide)- piperazine.

10. A compound of claim 5 which is N-[SH-dibenzo- (a,d)cyclohepten lO-yl]-piperazine-N'-yl-chlorophenylcarboxamide.

References Cited UNITED STATES PATENTS 3,290,313 12/1966 Cusic et al. 260268 3,320,259 5/1967 Cusic et al. 26O268 3,325,497 6/1967 Fouche 260-268 3,377,344 4/1968 Cusic et a1 260-268 3,457,264 7/1969 Viterbo et al 260268 3,459,745 8/1969 Fouche 260268 DONALD G. DA'US, Primary Examiner US. Cl. X.R.

(5/69) UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 575, 9 Dated April 20, 1971 Invent0r(s) Michele Mastursi, Sabine Lembo and Rene Viterbo It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 7' reads "2.2 ml. (33 mmol. acrylonitrile were dissolved in" and should read "1 ml (8.2 mmol) phenylisothiocyanz dissolved in" Signed and sealed this 9th day of November- 1971 (SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GO'ITSCHALK Attesting Officer Acting Commissioner of Patent 

